The E1795 is almost certainly the development valve that became the U101 indirectly heated half wave rectifier introduced in the 1940s. The paper label gives the heater as 50 Volts at 0.1 Amps and observation confirmed that the pin-out was the same.
The shiny black plastic spigot is essentially an M-OV feature (Mullard, Continental and US equivalents were all fitted with metal spigots).
The rectifier is designed for use in universal equipment with a series heater chain.
The maximum reservoir capacitor is 32 µF and the minimum series resistance has to be 100 Ohms.
The label shows that this was a product of M-OV and this unit is serial number 107.
The anode has a small front to back dimension of about 2 mm.
The blackened anode is 18 mm wide.
Thanks to Steve Jordan for donating this valve to the museum.
The wide glass tube envelope is 32 mm in diameter and, excluding the B8B base pins, is 57 mm tall.